阿翔编程学-webservice过滤器

过滤器类

package baseinfo.com.windtec.offline.server.baseinfo;

import java.io.IOException;

import java.util.ArrayList;
import java.util.List;
import java.util.StringTokenizer;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.servletexception;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

/**
 * 用于检测用户是否登陆的过滤器，如果未登录，则重定向到指的登录页面<p>
 * @author CaoXiang
 * @version 1.0
 */
public class UserFilter implements Filter {
 
 //过滤器配置对象
 protected FilterConfig filterConfig = null;
 
 //导向到该页面
 private String redirectURL = null;
 
 //不接受过滤的地址
 private List notCheckURLList = new ArrayList();
 
 //session对象中的key值
 private String sessionKey = null;

 /**
  * 过滤
  */
 public void doFilter(
  ServletRequest servletRequest,
  ServletResponse servletResponse,
  FilterChain filterChain)
  throws IOException,servletexception {
  HttpServletRequest request = (HttpServletRequest) servletRequest;
  HttpServletResponse response = (HttpServletResponse) servletResponse;

  HttpSession session = request.getSession();
  if (sessionKey == null) {
   filterChain.doFilter(request,response);
   return;
  }
  if ((!checkRequestURIIntNotFilterList(request))
   && session.getAttribute(sessionKey) == null) {
   response.sendRedirect(request.getcontextpath() + redirectURL);
   return;
  }
  filterChain.doFilter(servletRequest,servletResponse);
 }

 /**
  * 对象的销毁
  */
 public void destroy() {
  notCheckURLList.clear();
 }

    /**
     * 判断地址
     * @param request
     * @return
     */
 private boolean checkRequestURIIntNotFilterList(HttpServletRequest request) {
  String uri =
   request.getServletPath()
    + (request.getPathInfo() == null ? "" : request.getPathInfo());
  return notCheckURLList.contains(uri);
 }

 /**
  * filter初始化
  */
 public void init(FilterConfig filterConfig) throws servletexception {
  this.filterConfig = filterConfig;
  redirectURL = filterConfig.getinitParameter("redirectURL");
  sessionKey = filterConfig.getinitParameter("checkSessionKey");
  String notCheckURLListStr =
   filterConfig.getinitParameter("notCheckURLList");
  if (notCheckURLListStr != null) {
   StringTokenizer st = new StringTokenizer(notCheckURLListStr,";");
   notCheckURLList.clear();
   while (st.hasMoretokens()) {
    notCheckURLList.add(st.nextToken());
   }
  }
 }
 
}
web.xml配置

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems,Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app id="WebApp">
 <!-- WebService服务管理程序 -->
 <display-name>offlineserver</display-name>
 <filter>
           <filter-name>UserFilter</filter-name>
           <filter-class>baseinfo.com.windtec.offline.server.baseinfo.UserFilter</filter-class>
           <!-- 需检查的在 Session 中保存的关键字 -->
           <init-param>
                 <param-name>checkSessionKey</param-name>
                 <param-value>user</param-value>
           </init-param>
           <!-- 不做检查的URL列表，以分号分开，并且 URL 中不包括 contextpath -->
           <init-param>
                 <param-name>notCheckURLList</param-name>
                 <param-value>/index.jsp</param-value>
           </init-param>
           <!-- 如果用户未登录，则重定向到指定的页面，URL不包括 contextpath -->
           <init-param>
                 <param-name>redirectURL</param-name>
                 <param-value>/index.jsp</param-value>
           </init-param>
     </filter>
      <filter-mapping>
           <filter-name>UserFilter</filter-name>
           <url-pattern>/*</url-pattern>
     </filter-mapping>
    <!-- 用户登陆验证服务 -->
 <servlet>
  <servlet-name>user_com_windtec_offline_server_user_LoginServiceImp</servlet-name>
  <servlet-class>user.com.windtec.offline.server.user.LoginServiceImp</servlet-class>
  <load-on-startup>1</load-on-startup>
 </servlet>
 <!-- 默认显示的首页 -->
 <welcome-file-list>
  <welcome-file>index.html</welcome-file>
  <welcome-file>index.htm</welcome-file>
  <welcome-file>index.jsp</welcome-file>
  <welcome-file>default.html</welcome-file>
  <welcome-file>default.htm</welcome-file>
  <welcome-file>default.jsp</welcome-file>
 </welcome-file-list>
</web-app>

代码如上，希望对大家有帮助